sem_acquire

(PHP 4, PHP 5)

sem_acquire — Acquire a semaphore

Description

bool sem_acquire ( resource $sem_identifier )

sem_acquire() blocks (if necessary) until the semaphore can be acquired. A process attempting to acquire a semaphore which it has already acquired will block forever if acquiring the semaphore would cause its maximum number of semaphore to be exceeded.

After processing a request, any semaphores acquired by the process but not explicitly released will be released automatically and a warning will be generated.

Parameters

sem_identifier

sem_identifier is a semaphore resource, obtained from sem_get().

Return Values

Returns TRUE on success or FALSE on failure.

See Also

• sem_get() - Get a semaphore id
• sem_release() - Release a semaphore